The EXT4 file-system today deprecated its journaled mode of the “data=journal” mount option. Following its deprecation, this mode is planned for removal in the year 2028.
The data=journal mode for EXT4 is where all file data and metadata is written to the file-system’s journal before being committed to the main file-system. In the event of a crash or power loss, the journal can then be replayed to recover the data.
The EXT4 data=journal mode is great for those very concerned about data integrity and safety but comes with significant hits to the write performance compared to the default ordered (data=ordered) mode or data=writeback. Using the journaled mode also disables delayed allocation and Direct I/O support.
EXT4 journal deprecated
Per today’s Git merge for Linux 7.3, the EXT4 data=journal feature is deprecated and support for it will be removed in early 2028 following the 2027 Linux LTS kernel version.
No, the journal is not deprecated. Only data journaling is.
Metadata is still journaled and is what most people have been using all this time.
But why they need to remove it? Maybe just left it as a non-recommended option or just create an alternative. A great amount of people, like me for example, have a volatile enviroment that makes this a need.
Although I do prefer Btrfs for that task, I understand why some people need it in Ext4.
But why they need to remove it?
Most likely maintainers are looking to reduce the maintenance burden produced by a feature that had very low uptake (assuming, as others are saying, that it’s only data journalling and not metadata journalling that’s being removed).
Yeah, it might be that and that sounds fair, but still they could just make something like an external extension or module or something like that, or outright looking for someone who could make a more modern, maintenable, fast, lightweight and efficient alternative (using, i.e. io_uring).
Although I do prefer Btrfs for that task, I understand why some people need it in Ext4.
i was going to say something along these lines – we switched at a previous last shop to something more reliable and it got rid of our problems, but our fleet was probably newer and smaller than yours; around 5k debian 8/9 bare iron servers back around 2017.
Okay, but no mention of alternative modes of operation for “those very concerned about data integrity and safety”?
What reason is there to use EXT4 if not for the journal?
Just use F2FS or BTRFS at that point. (or ZFS if you’re fine with out-of-tree)
They are not removing the journal.
Ahem…
Per today’s Git merge for Linux 7.3, the EXT4 data=journal feature is deprecated and support for it will be removed in early 2028 following the 2027 Linux LTS kernel version.
data=journal is just one mode of journaling. Not the entire feature.
Journaling all of the data is very expensive and slow and no one was using it.
Metadata journaling as always the main feature and is still present.
Some people was using it, you’re being dishonest.
Anyway, yeah, I misread, not all journaling is data=journal.
Wasn’t the journal the main selling point in the transition from EXT2 to EXT3? This seems kinda backwards, what even is the rational?
The metadata journal is still there. Most people are not journaling their data, it’s too slow.
Ah, I see! From googling “data=ordered” is the default and does what you said. Still, why not leave it for those that want it?
Maintenance is not free? They still have to test it at the very least.
Yeah, but I thought the philosophy was not to break userspace. I’m fine with the removal if absolutely nobody uses it, but some have commented here being users of the feature
Hmm, I don’t really think this counts as user space. This is a kernel configuration parameter. User facing for sure, so a bit of gray area perhaps.
That’s too bad. It was great for use as a root fs on VMware when you had an unreliable NFS storage. Kept every VM from needing an FSCK on recovery.
